DA 42 accident

Hi.

Here in Germany we had an accident with a brand new DA 42 in Speyer
(EDRY) on 3-4-07 during take off.

It seems, that the battery was down and both engine were started with
remote power.
After take off when retracting the gear, the props feathered and both
engines stopped.

You can read about that accident in German (sorry) in
www.pilotundflugzeug.de

First hearing about that accident and the background, I could not
believe it.

Karl

Interesting! I have been a vocal proponent of the diesel movement for
years, but I'm also troubled by the real lack of technical discussion and
analysis of the Thielert and SMA products available here (USA). This past
Tues and Wed at Sun N Fun, I made several trips back and forth between the
Miami based Thielert retrofitters (near the SAAB tent) and the Superior
tent, hoping to chat with the Thielert technical expert. Each time I was
told that he (the only expert there) was at the other tent. I was hoping to
get the details of what problems they were experiencing with the 1.7 block;
to make them retool to the 2.0 block with no performance increase. Left to
my own imagination, I would not want to be flying behind the 1.7 at this
point forward.

Also, the Thielert boys seem to have committed to very modern electronic
control systems to manage their engine (lots of MB three pointed star
emblems on the electrical connectors). I asked last year at the AOPA Tampa
show if the engine had a Limp Home Mode for a major electrical system
failure. I got a quizical look and a promise of a call to my cell number
once "the only expert at that show" returned to the booth,... still waiting.

Too bad,... looks to me like they have a good product, but if they keep
hiding from the flying public they'll lose the trust factor fast.

Lastly, to speak to this DA-42 problem directly, I recall reading in the
early (post certification) period of the 1.7 in the euro version DA-40, they
experienced two documented in-flight electric control module failures which
resulted in engine shutdowns with unsuccesful restart. Just speculating
he Looks like if the battery was dead and the LG motor surge was too much
for the alternators..., well, lets not speculate....


"Karl-Heinz Kuenzel" wrote ...
Here in Germany we had an accident with a brand new DA 42 in Speyer
(EDRY) on 3-4-07 during take off.

It seems, that the battery was down and both engine were started
with remote power.
After take off when retracting the gear, the props feathered and both
engines stopped.

"Mike Isaksen" wrote in message newsHRWh.10911$bZ2.2688@trndny01...
: Interesting! I have been a vocal proponent of the diesel movement for
: years, but I'm also troubled by the real lack of technical discussion and
: analysis of the Thielert and SMA products available here (USA). This past
: Tues and Wed at Sun N Fun, I made several trips back and forth between the
: Miami based Thielert retrofitters (near the SAAB tent) and the Superior
: tent, hoping to chat with the Thielert technical expert. Each time I was
: told that he (the only expert there) was at the other tent. I was hoping to
: get the details of what problems they were experiencing with the 1.7 block;
: to make them retool to the 2.0 block with no performance increase. Left to
: my own imagination, I would not want to be flying behind the 1.7 at this
: point forward.
:
:

Doesn't the 1.7 have a throw away TBO-like limitation that is very low?

Karl-Heinz Kuenzel wrote:
Hi.

Here in Germany we had an accident with a brand new DA 42 in Speyer
(EDRY) on 3-4-07 during take off.

It seems, that the battery was down and both engine were started with
remote power.
After take off when retracting the gear, the props feathered and both
engines stopped.

You can read about that accident in German (sorry) in
www.pilotundflugzeug.de

First hearing about that accident and the background, I could not
believe it.

I don't even know where to start. How can an aircraft, that depends on
electrical power for the operation of it's engines, be airworthy without
fully redundant electrical systems? While in this particular case the pilot
might have noticed the problem, had he meticuously follow procedures and
started the second engine at the plane's own power, it is quite easy to find
failure modes that would go unnoticed inflight, yet cause double engine
failure at the instant the gear is lowered on final. Lead batteries are
known to occasionally go flat suddenly, once the buildup of oxide makes
contact between the lead elements. Happened to me in the car once. The
engine (a diesel with mechanical injection pump) ran happily without me even
noticing the failure until I shut it down. When I turned the power back on
again, not even the lights in the dashboard would light up, it was
completely and utterly dead.

I would never have thought that they cut corners like that at Diamond. I
Hope this will not create a lot of mistrust in aerodiesels, as it is not a
diesel issue. I guess you could call it a FADEC issue if you wanted, however
it really is an issue of redundancy of essential systems, and easily
solveable as such.

regards,
Friedrich

Friedrich Ostertag schrieb:
Karl-Heinz Kuenzel wrote:
Hi.

Here in Germany we had an accident with a brand new DA 42 in Speyer
(EDRY) on 3-4-07 during take off.

It seems, that the battery was down and both engine were started with
remote power.
After take off when retracting the gear, the props feathered and both
engines stopped.

You can read about that accident in German (sorry) in
www.pilotundflugzeug.de

First hearing about that accident and the background, I could not
believe it.

I don't even know where to start. How can an aircraft, that depends on
electrical power for the operation of it's engines, be airworthy without
fully redundant electrical systems? While in this particular case the pilot
might have noticed the problem, had he meticuously follow procedures and
started the second engine at the plane's own power, it is quite easy to find
failure modes that would go unnoticed inflight, yet cause double engine
failure at the instant the gear is lowered on final. Lead batteries are
known to occasionally go flat suddenly, once the buildup of oxide makes
contact between the lead elements. Happened to me in the car once. The
engine (a diesel with mechanical injection pump) ran happily without me even
noticing the failure until I shut it down. When I turned the power back on
again, not even the lights in the dashboard would light up, it was
completely and utterly dead.

I would never have thought that they cut corners like that at Diamond. I
Hope this will not create a lot of mistrust in aerodiesels, as it is not a
diesel issue. I guess you could call it a FADEC issue if you wanted, however
it really is an issue of redundancy of essential systems, and easily
solveable as such.

regards,
Friedrich


Friedrich,

I did not believe it either. Maybe I am getting to old. For me a diesel
would run forever until you cut the fuel.

What those people did. They just started #1 and #2 (which was NOT ok) on
external power. And everything looked ok. Until they retracted the
landing gear....

I posted that story in our German newsgroup and nobody seemed to be
interested in that issue. I was just curious, if someone here is interested.

regards Karl

On Apr 23, 12:51 pm, "Neil Gould" wrote:
Recently, Friedrich Ostertag posted:



Karl-Heinz Kuenzel wrote:
Hi.

Here in Germany we had an accident with a brand new DA 42 in Speyer
(EDRY) on 3-4-07 during take off.

It seems, that the battery was down and both engine were started with
remote power.
After take off when retracting the gear, the props feathered and both
engines stopped.

You can read about that accident in German (sorry) in
www.pilotundflugzeug.de

First hearing about that accident and the background, I could not
believe it.

I don't even know where to start. How can an aircraft, that depends on
electrical power for the operation of it's engines, be airworthy
without fully redundant electrical systems? While in this particular
case the pilot might have noticed the problem, had he meticuously
follow procedures and started the second engine at the plane's own
power, it is quite easy to find failure modes that would go unnoticed
inflight, yet cause double engine failure at the instant the gear is
lowered on final. Lead batteries are known to occasionally go flat
suddenly, once the buildup of oxide makes contact between the lead
elements. Happened to me in the car once. The engine (a diesel with
mechanical injection pump) ran happily without me even noticing the
failure until I shut it down. When I turned the power back on again,
not even the lights in the dashboard would light up, it was
completely and utterly dead.

I would never have thought that they cut corners like that at
Diamond. I Hope this will not create a lot of mistrust in
aerodiesels, as it is not a diesel issue. I guess you could call it a
FADEC issue if you wanted, however it really is an issue of
redundancy of essential systems, and easily solveable as such.

I have a somewhat different take on this event. It appears to me that the
pilot didn't sufficiently understand his aircraft or the implications of
the symptoms he observed. Knowing that there was insufficient power to
start the engines, that the engine & prop controls were dependent on
electric power and that the landing gear used an electric motor would have
stopped me from taking off until the battery/electrical system problem was
addressed. I don't find it surprising that the props feathered in this
situation, and would even say that it would be the expected behavior,
rather than a fluke of some kind. I would find it surprising if Diamond
doesn't have adequate information about their flight systems in the POH to
inform the pilot of this possibility.

Regards,

Neil

I just received an e-mail today from Diamond explaining the situation.
Since the engines are FADEC controlled, the dead battery did not have
enough power to retract the landing gear and keep the engines going.
The e-mail also stated that Diamond is looking into making some
changes.

Cary (DA42 owner)

Neil Gould schrieb:
Recently, Friedrich Ostertag posted:

Karl-Heinz Kuenzel wrote:
Hi.

Here in Germany we had an accident with a brand new DA 42 in Speyer
(EDRY) on 3-4-07 during take off.

It seems, that the battery was down and both engine were started with
remote power.
After take off when retracting the gear, the props feathered and both
engines stopped.

You can read about that accident in German (sorry) in
www.pilotundflugzeug.de

First hearing about that accident and the background, I could not
believe it.
I don't even know where to start. How can an aircraft, that depends on
electrical power for the operation of it's engines, be airworthy
without fully redundant electrical systems? While in this particular
case the pilot might have noticed the problem, had he meticuously
follow procedures and started the second engine at the plane's own
power, it is quite easy to find failure modes that would go unnoticed
inflight, yet cause double engine failure at the instant the gear is
lowered on final. Lead batteries are known to occasionally go flat
suddenly, once the buildup of oxide makes contact between the lead
elements. Happened to me in the car once. The engine (a diesel with
mechanical injection pump) ran happily without me even noticing the
failure until I shut it down. When I turned the power back on again,
not even the lights in the dashboard would light up, it was
completely and utterly dead.

I would never have thought that they cut corners like that at
Diamond. I Hope this will not create a lot of mistrust in
aerodiesels, as it is not a diesel issue. I guess you could call it a
FADEC issue if you wanted, however it really is an issue of
redundancy of essential systems, and easily solveable as such.

I have a somewhat different take on this event. It appears to me that the
pilot didn't sufficiently understand his aircraft or the implications of
the symptoms he observed. Knowing that there was insufficient power to
start the engines, that the engine & prop controls were dependent on
electric power and that the landing gear used an electric motor would have
stopped me from taking off until the battery/electrical system problem was
addressed. I don't find it surprising that the props feathered in this
situation, and would even say that it would be the expected behavior,
rather than a fluke of some kind. I would find it surprising if Diamond
doesn't have adequate information about their flight systems in the POH to
inform the pilot of this possibility.

Regards,

Neil




OK Neil.

You find it in the article.

POH - Under - abnormal operating procedures - 4B.7 STARTING ENGINE WITH
EXTERNAL POWER - #13 Opposite engine ..... START WITH NORMAL PROCEDURE

That is it.

Karl

Recently, Friedrich Ostertag posted:

Karl-Heinz Kuenzel wrote:
Hi.

Here in Germany we had an accident with a brand new DA 42 in Speyer
(EDRY) on 3-4-07 during take off.

It seems, that the battery was down and both engine were started with
remote power.
After take off when retracting the gear, the props feathered and both
engines stopped.

You can read about that accident in German (sorry) in
www.pilotundflugzeug.de

First hearing about that accident and the background, I could not
believe it.

I don't even know where to start. How can an aircraft, that depends on
electrical power for the operation of it's engines, be airworthy
without fully redundant electrical systems? While in this particular
case the pilot might have noticed the problem, had he meticuously
follow procedures and started the second engine at the plane's own
power, it is quite easy to find failure modes that would go unnoticed
inflight, yet cause double engine failure at the instant the gear is
lowered on final. Lead batteries are known to occasionally go flat
suddenly, once the buildup of oxide makes contact between the lead
elements. Happened to me in the car once. The engine (a diesel with
mechanical injection pump) ran happily without me even noticing the
failure until I shut it down. When I turned the power back on again,
not even the lights in the dashboard would light up, it was
completely and utterly dead.

I would never have thought that they cut corners like that at
Diamond. I Hope this will not create a lot of mistrust in
aerodiesels, as it is not a diesel issue. I guess you could call it a
FADEC issue if you wanted, however it really is an issue of
redundancy of essential systems, and easily solveable as such.

I have a somewhat different take on this event. It appears to me that the
pilot didn't sufficiently understand his aircraft or the implications of
the symptoms he observed. Knowing that there was insufficient power to
start the engines, that the engine & prop controls were dependent on
electric power and that the landing gear used an electric motor would have
stopped me from taking off until the battery/electrical system problem was
addressed. I don't find it surprising that the props feathered in this
situation, and would even say that it would be the expected behavior,
rather than a fluke of some kind. I would find it surprising if Diamond
doesn't have adequate information about their flight systems in the POH to
inform the pilot of this possibility.

Regards,

Neil

Recently, Karl-Heinz Kuenzel posted:

Neil Gould schrieb:
I have a somewhat different take on this event. [...]
I don't find it
surprising that the props feathered in this situation, and would
even say that it would be the expected behavior, rather than a fluke
of some kind. I would find it surprising if Diamond doesn't have
adequate information about their flight systems in the POH to inform
the pilot of this possibility.


OK Neil.

You find it in the article.

My Deutsch is far too rusty to find it in the article. ;-)

POH - Under - abnormal operating procedures - 4B.7 STARTING ENGINE
WITH EXTERNAL POWER - #13 Opposite engine ..... START WITH NORMAL
PROCEDURE

That is it.

That's fine for starting the engines, but that isn't the only issue, is
it?

Is there nothing in the POH about the electrically powered items (landing
gear, FADEC, etc.)? If there is, it shouldn't require an EE degree to
realize that one should be concerned about the condition of the batteries,
charging, etc. if one has to "jump start" the engine, or to realize that
something critical is in need of attention.

Maybe I'm just an overly cautious type. ;-)

Neil

Recently, Cary posted:

I just received an e-mail today from Diamond explaining the situation.
Since the engines are FADEC controlled, the dead battery did not have
enough power to retract the landing gear and keep the engines going.
The e-mail also stated that Diamond is looking into making some
changes.

Cary (DA42 owner)

The actual wording of that email would be interesting. I'd think that the
FADEC keeps the fuel flow and props configured, and that the current draw
of the landing gear motor(s) probably shut the FADEC down due to low
voltage. While that could be addressed with a different power
configuration (a separate battery for the FADEC, for example), it may also
introduce more failure modes and more factors to take into consideration
during pre-flight.

Neil (NOT a DA42 owner)